A high-intensity discharge (HID) lamp uses a plasma arc to produce light. HID lamps have been widely used as a viable option for producing efficient illumination for many different types of applications requiring a light source. When compared with fluorescent and incandescent lamps, HID lamps have higher luminous efficacy since a greater proportion of input energy is converted into visible light as opposed to heat. In general, a HID lamp produces light by means of an electric arc between electrodes housed inside a discharge vessel (also known as an arc tube or burner) typically filled with both gas and metal salts, whereby the gas facilitates the arc's initial strike. Once the arc is started, it heats and evaporates the metal salts forming a plasma, which greatly increases the intensity of light produced by the arc and reduces its power consumption. A HID lamp may require high voltage to initialize the arc.